This was a song event by minor seiyuu and idols/cosplayers.
It seems to take place once or twice a month, but this was the second
time that I went. There were around 50 people in the crowd.

I went to watch Mizuno Saya.

The event flowed as follows.

Pastel (1 song)

Kisaragi Marii (1 song)

Mizuno Saya (2 songs)

Sekine Keiko (2 songs)

Puchi Milk (medley)

Sparkle Princess (1 song)

Konatsu Minato (2 songs)

Yanagi Mao (medley, 1 song)

Mizuno Saya sang her two songs "Tsuki Akari" and "Princess Kiss".
Her
debut CD "Tsuki Akari"
containing these two songs went on sale after this event.
This was the first time I heard these songs, and they were very good.
The music and arrangement is much better than I had expected for a
song produced by such a minor company.
Saya wrote the lyrics for these songs.

Puchi Milk is a unit made up of two cosplayers Niina Sakuya and Kujou Ruka.
Their medley had songs from Tokimeki Memorial, Kita he, and Fancy Lala.

Yanagi Mao said that her song "ICTL" played as BGM during one episode
of the anime Ultimate Girl.

Photos with flash allowed. Video and audio recording not allowed.

photo notes

I took 1102 photos with my 20D, with 293 photos worth keeping.
The photo counts per girl was as follows.